A JSON object containing additional, value-type-dependent properties.
<p>For variables of type <code>Object</code>, the following properties are returned:</p>
<ul>
  <li>
    <code>objectTypeName</code>: A string representation of the object's type name.
  </li>
  <li>
    <code>serializationDataFormat</code>: The serialization format used to store the variable.
  </li>
</ul>